Process for manufacturing beryllium alloys



Patented June 30, 1936 UNITED STATES PATENT OFFICE PROCESS 'FORMANUFACTURING BERYLLIUM ALLOYS notation of Delaware Application June 26,1934,

No Drawing.

Serial No. 732,435

16 Claims.

This invention relates to a method for the direct manufacture of alloysof beryllium, in particular those of beryllium with copper, nickel, andiron.

Since the early work of Lebeau, in 1898, it has been known that thealloys of beryllium with copper and similar heavy metals have greatvalue commercially, and more recent work has shown that the propertiesof such alloys are greatly enhanced by appropriate heat treatment. Therehas therefore been a great demand for such alloys, preponderant in theheavy metal, with beryllium content in the lower rangesseldom over Thesimple, laboratory method of alloy formation, direct fusion of the twometals, has been found, when transferred to a commercial scale, open tothe objection that the losses are high and the cost of elementaryberyllium metal is excessively high.

We have foundthat success can be attained readily if massive metal isused as a cathode electrode material; further, if this metal cathode isso suspended that any liquid alloy formed on its surface by theprocedure of our invention can flow down readily away from the cathodeinto an electrically neutral area, operation can be made continuous, ifdesired.

In our invention, we suspend a massive cathode of the metal to bealloyed with beryllium in an electrolytic cell in which beryllium isbeing electrodeposited. As electrolyte in the cell, we may use any ofthose regularly in use for beryllium manufacture-Beck dissolved in NaCl,Na2BeF4, beryllium oxyfluoride dissolved in other fluorides, etc.;indeed, the process is essentially independent of the electrodepositionmedium. The only requirement is that the bath (and, of course,

with it the cathode) be maintained at a temperature below the meltingpoint of the cathode but above that at which the lowest melting point(860 C. with copper) eutectic of the particular alloy which that metalforms with beryllium on electrolysis, melts. In the case of copper, asan example, it is best to operate in the 9001000 C. range; in this rangethe deposition of beryllium on the solid copper causes surface alloyingwhich immediately causes the corresponding amount of alloy to turnliquid because of its lower melting point; this liquid will liquate awayfrom the electrode, baring new surfaces continuously. In this manner,and at this temperature range, a copper-beryllium alloyof about 2 toabout 6% beryllium can readily be obtained.

For practical reasons, of course, it is best to have two or more anodesfor the cathode, but this is not at all necessary to the invention,though helping in actual practice to cause regular, even attack on thecathode. Attack on the cathode proceeds, we have found, with both aBeClz or a NazBeFr bath, at a steady regular rate, a solid rod cathodemerely tending to pencil as the electrolysis proceeds.

Naturally, as the newly-formed liquid alloy liquates away from thecathode of which it was just a part, it is brought to an electricallyneutral-or primarily neutral-portion of the cell, so as to avoidcounter-reactions. From this point (generally the bottom of the cell,away from both the cathode and the anode) the liquid alloy may readilybe tapped away, either intermittently or, preferably, in continuousstream.

By combining this invention with that de scribed in a co-pendingapplication of H. C. Claflin, Serial No. 732,436, wherein there isdescribed, a process for the production of beryllium in elementary oralloy form by the addition of ammonium beryllium fluoride to an alkalior alkaline earth metal fluoride bath and electrolyzed, we have attaineda very convenient and effective procedure for the continuous productionof commercial copper-beryllium alloys the electrolyz able salt being fedin continuously or at sumciently frequent intervals, and the final alloybeing also tapped off the cell continuously or at sufliciently frequentintervals.

In such procedure, there is nothing accumulating in the bath in that thefluorine and ammonium fluoride are evolved as gases and the berylliumtapped off in the alloy produced. Where the electrolyte is, for example,NazBeFr there is a gradual accumulation of NaF in the bath, so thatcontinuous operation cannot be so simply and economically obtained. Hereit is necessary to remove a portion of the bath from time to time whichinvolves a. loss in values, and other objections. The periods ofoperation in such procedure must therefore be much shorter than possiblewhen using ammonium beryllium fluoride, which may be months.

While copper has been used regularly as an example in the descriptiongiven above, it can readily be seen that the process lends itselfequally well to other metals with which beryllium alloysmost importantcommercially being iron and nickel.

In all cases, the metal salt or salts of the bath should be moreelectropositive than beryllium.

We also prefer to tap off the alloy from the cell in an atmosphere inertto beryllium or the alloy, flowing the same into molds. This may beconveniently done, for example, by placing a hood over the cell andintroducing an inert gas such as argon or helium. In such case, thetapping may be done by a rod insertable through the hood, especially iithe pressure within the hood be kept slightly above atmospheric to avoidinfiltration. Obviously-then; may be a number of different ways in whichthe alloy may be tapped from the cell and kept out of contact withoxygen or nitrogen or other contaminant.

A further advantage in adding the beryllium in the form of ammoniumberyllium fluoride is that the proportion of 38F: in the bath can beraised above the point where anode effect objectionably sets in.

Having described our invention, we claim: 1. The process of formingalloys of beryllium characterized by the electrodeposition of berylliumon to an unmolten cathode of the second metal at a temperature below themelting point of that metal and above the melting point of "the alloyeutectic.

2. The process of forming copper-beryllium alloys characterized by theelectrodeposition oi beryllium on to an unmolten copper cathode at atemperature below the melting point of copper and above the meltingpoint of the copper-beryllium alloy eutectic.

3. The process of forming copper-beryllium alloys characterized by theelectrolysis of electrolyzable beryllium compounds, using a cathode ofmassive copper, said electrolysis proceeding at a temperature between860 C. and 1083 C. v

4. The process of forming alloys of beryllium characterized by theelectrodeposition of beryllium eutectic, the resultant fluid alloy beingremoved to an electrically neutral point.

6. The process of forming copper-beryllium alloys characterized by theelectrolysis of electrolyzable beryllium compounds, using a cathodeof'massive copper, said electrolysis proceeding at a temperature between860 C. ,and 1083 C., the resultant fluid alloy being removed to anelectrically neutral point.

7. The process of forming alloys of beryllium characterized by theelectrodeposition of beryllium on to an unmolten cathode of the secondmetal at a. temperature below the melting point of that metal and abovethe melting point of the alloy eutectic, the resultant fluid alloybeing'removed, as formed, from the electrolytic field of action.

8. The process of forming copper-beryllium alloys characterized by theelectrodeposition of beryllium on to an unmolten copper cathode at atemperature below the. melting point of copper and above the meltingpoint of the copper-beryllium eutectic, the resultant fluid alloybeing-removed, as formed, from the electrolytic held of action.

9. The process of forming copper-beryllium alloyscharacterized by theelectrolysis of electrolyzable beryllium compounds, using a cathode ofmassive copper, said electrolysis proceeding at a temperature between860 C. and 1083 C., the resultant fluid alloy being removed, 155 formed,from the electrolytic fleld of action.

10. The process of forming alloys of beryllium characterized by theelectrodeposition of beryllium on to an umnolten cathode of the secondmetal at a temperature below the melting point of that metal and abovethe melting point of the alloy eutectic, the resultant fluid alloy beingremoved, substantially as formed, from the electrolysis cell.

11. The process of forming copper beryllium alloys characterized by theelectrodeposition oi' beryllium on to an unmolten copper cathode at atemperature below the melting oint of copper and above the melting pointof the copper-beryllium alloy eutectic, the resultant fluid alloy beingremoved, substantially as formed, from the electrolysis cell.

12. The process of forming copper-beryllium alloys characterized by theelectrolysis of electrolyzable beryllium compounds, using a cathode ofmassive copper,said electrolysis proceeding at a temperature between 860C. and 1088" C., the resultant fluid alloy being removed, substantiallyas formed, from the electrolysis cell.

13. The continuous process of producing an alloy o1 beryllium andanother metal or metals which consists in substantially continuouslyintroducing an electrolyzable compound of beryllium into an electrolyticcell having a cathode of such metal or metals, operating at atemperature below the melting point oi. the cathode but above themelting point of the eutectic of the alloy formed, and in substantiallycontinuously withdrawing the alloy' produced.

14. The continuous process of producing an alloy 'of beryllium andanother metal or metals which consists in substantially continuouslyintroducing an electrolyzable compound of beryl: lium into anelectrolytic cell having a cathode of such metal or metals, operating ata temperature below the melting point oi. the cathode but at which thealloy formed by the electrodeposition of the beryllium on the cathodeliquates away, collecting the liquated alloy in an electrically neutralportion of the cell, and substantially continuously withdrawing suchalloy.

15. The continuous process of producing an alloy oi beryllium andanother metal or metals which consists in substantially continuouslyintroducing an electrolyzable compound of beryllium into an electrolyticcell having a cathode of such metal or metals, operating at atemperature below the melting point of the cathode but at which thealloy Iormed by the-electrodeposition of the beryllium on the cathodeliquates away, collecting the liquated alloy in an electrically neutralportion 01. the cell, and substantially continuously withdrawing suchalloy in an atmosphere inert to the beryllium or the alloys.

16. The process of obtaining alloys of beryllium which includes thesteps of adding ammonium beryllium fluoride to a fusion of the fluoridesof one or more metals more electropositive than beryllium, subjectingthe mixed fusion to electrolysis, using a cathode of the metal about tobe

